The present invention relates to the image processing, in particular to a processing method of pressure-sensitive light and shadow imaging system and formed footprint image.
The existing imaging system is based on the light ray reflected by the object, and the formed image is dimensional, and the size of pressure can't be observed on the displayed plane picture. The pressure distribution of texture substance, e.g. footprint image, plays a critical role in the criminal investigation.
With the development of existing technology, the handwriting electronic imaging system is also highly developed, but the handwritings can only be displayed on electronic equipment with existing technology, and its pressure distribution and stroke order can't be inquired and saved. The stroke order and pressure distribution are mainly studied to identify handwritings in the handwriting comparison system and handwriting inquiry system.
Now, the static picture shoot by camera directly and subsequent digital processing are available for collecting the footprint patterns, but the disadvantages of such processing mode are that the footprint image obtained is incomplete, and the heel and toe images are insufficient or incorrect. The other method to collect footprint pattern is to first acquire footprint, take pictures or scan, and finally execute digital processing, but the disadvantages of such method are that additional materials required for stamp are required, and the digitalized footprint image is available through several steps. Therefore, in most cases, the relatively advanced footprint collection instrument is adopted to collect the footprint image which is shoot by camera and saved to a series of single-frame images. A series of single-frame images are integrated into a complete footprint image, which can digitalize rapidly and directly, and save the materials required for stamped footprint and the time of converting the stamped footprint into digital footprint.
It shall make the rear foot (barefoot or with socks or shoes) first contact the collection instrument, put down the middle to make it contact the collection instrument and finally lift heel to make the forefoot contact the collection instrument so as to get a complete footprint image when the flat image information of footprint is collected with footprint collection instrument. During the whole process, the contact site of sole and collection instrument is from rear foot to forefoot gradually. The footprint image collected by collection instrument is a multi-frame image, and only a part of footprint image is displayed on each frame image. Based on the need of footprint digitalization, such multi-frame image must be integrated into a complete footprint image.
The noise interference is present on the data background of footprint collection instrument after a long time due to external factors, so that the footprint image collected contain noise.